manganese oxidation

Edge evidence

• multicopper oxidase enables manganese oxidation RO:0002327

  Multicopper oxidases catalyze the Mn(II) → Mn(III/IV) oxidation step.

  • DOI:10.1016/j.tim.2005.07.009 Tebo et al. support bacterial Mn(II) oxidation via a multicopper- oxidase mechanism.
• manganese oxidation produces Mn(III/IV) oxides METPO:2000202

  The metabolism deposits biogenic Mn(III/IV) oxides.

  • DOI:10.1146/annurev.earth.32.101802.120213 Tebo et al. characterize the formation and properties of bacterially produced Mn(III/IV) oxides.
• molecular oxygen (O2) enables manganese oxidation RO:0002327

  O2 serves as the direct oxidant enabling multicopper-oxidase-mediated Mn(II) oxidation.

  • DOI:10.1021/jacs.3c06537 Some microbes can use O2 directly via multicopper oxidase (MCO) enzymes for Mn(II) oxidation.
• manganese oxidation produces Mn(III)(OH)Mn(III) intermediate METPO:2000202

  A cooperative two-electron oxidation step produces a Mn(III)(OH)Mn(III) intermediate.

  • DOI:10.1021/jacs.3c06537 Cryo-EM mechanistic model: a cooperative two-electron step producing a Mn(III)(OH)Mn(III) intermediate.
• Mn(III)(OH)Mn(III) intermediate disproportionates to form Mn(IV)(O)Mn(IV) intermediate

  Two Mn(III)(OH)Mn(III) species disproportionate to form Mn(IV)(O)Mn(IV).

  • DOI:10.1021/jacs.3c06537 Disproportionation of two Mn(III)(OH)Mn(III) species to form Mn(IV)(O)Mn(IV).
• Mn(IV)(O)Mn(IV) intermediate condenses into MnO2 nanoparticles

  Mn(IV)(O)Mn(IV) condenses en route to MnO2 nanoparticle release.

  • DOI:10.1021/jacs.3c06537 Mn(IV)(O)Mn(IV) is en route to MnO2, with release of MnO2 nanoparticles.
• MnO2 nanoparticles is a Mn(III/IV) oxides rdfs:subClassOf

  MnO2 nanoparticles are a form of the insoluble biogenic Mn(III/IV) oxide product.

  • DOI:10.1021/jacs.3c06537 MnO2 nanoparticles are the final insoluble Mn(IV) oxide biomineral product of the oxidation cascade.